Improvement in safety-latches



side of a door,

@than dimite.

c. WARD rIrInLD, or FRANKLIN, NEW HAMPSHIRE.

\ Letters Patent No. 107,895, dated4 October 4, 1870.

IMPROVEMENT IN SAFETY-LATCHES.-

Thechdulereferred tojn these lI.|etl:ers`1ate1:n: and making part of thesanixe.

To all whom it 'muy concern A `Be it known that I, J. WARD FIFIELD, of Franklin, in the county of Mern'mac and State of New Hampshire, have. invented a new and useful Improvement in Operating Safety-Latcl'ies; andfi do hereby declare that the following is vaf'full, clear, and cxactgdescription thereof', which kwill enable others skilled in the art to make and use the same, reference being had'to the accompanying drawing forming part of this specification.

. I This invention relates to a new andusefulinlprovement in operating safety-latches, whereby the latch may be moved, for locking or unlocking, by means of a key,'as` hereinafter described.

In the accompanying `drawing-- Figure l represents, au linside view of `the safetylatch, which isattached to'the inside of a door, so that the slot in the latch will tonto the square knob-spindle, and prevent it from being turned by `the door-V knob. i

Figure 2 is a section through the line :c x of g. 1. Figure 3 is a section through the line y y of dig. 1.

. .Similar lettersotjreerence indicate-.corresponding parts.

A is a plate or washer, which is fastened to the' Vinthrough which the spindleof a1mor tise knob-lock passes. l

B is the safety-latch, which is pivoted to the plate A at the point O. v At its other end there is a small knob, D, by which the latch is moved, so that the slot4 E will fit onto the knob-spindleof a mortiseflock, when itis desired to prevent the knob from being turned. y

The latch movesin a recess in the -Iim of the plate, which reccss,'j, ig..2, has a catch, g, over which the latch is passed when the spindle is locked, as seen in the drawing.

The latchv is a spring, and, to release it from the spindle, it is sprung over the catch and intothe long part u.of the recess f. This is done 'by the knob D, and the fastening is operated only on the inside.

.To accomplish .t-liis, by means of a kev from the outside, is the object of this invention.

For this purpose I make the latch-pivot C a pivot fora key, and make an orifice, h, through the latch. A portion of the bit of thegkey 'passes through this orih'ce h, and hooks onto the latch, as seen in iig. 3.

The latch being a spring, a slight lateral pressure n the key serves to raise the latch over the catch g, when it may be carried by the key from the spindle in the recess f, thus allowing the knob and spindle to be turned and the door unlocked. -The latch maybe operated from. the outside for either unlocking or locking the spindle, thus making the arrangement answer all the purposes of a good night-loc Having thusl described my invention,

I claim as new and vdesire 'to ysecure by Letters Patent- I and key-pivot C, whereby the latch may be operated from'the outside, by meansof a key, substantially as described.

2. Operating a spindle safety-latch from the out side of a door, by means of a key. v J. WARD FIFIELD.

Witnesses: N. H. SANBonN,

Y. L. SANBORN. 

